1. Field of the Invention
The present invention relates to an optical signal processor which processes light fed to an input port according to a wavelength of the light and then outputs the light from an output port.
2. Related Background of the Invention
An optical signal processor is equipped with a wavelength demultiplexer, which demultiplexes light in terms of wavelengths, and processes individual wavelengths of light demultiplexed in terms of wavelengths. An example of such an optical signal processor is a dispersion compensator which adjusts the chromatic dispersion of light according to the wavelength thereof (see, for example, Patent Document 1: Japanese Patent Application Laid-Open No. 2002-303805).
The optical signal processor (dispersion compensator) disclosed in Patent Document 1 can favorably be used for compensating for the chromatic dispersion of signal light in an optical communication system. In the optical signal processor, light to be subjected to dispersion compensation is inputted, and then is demultiplexed by a wavelength demultiplexer in terms of wavelengths. Thus wavelength-demultiplexed light components are reflected by a reflecting mirror, so as to be multiplexed by and outputted from the wavelength demultiplexer. Here, wavelength light components different from each other are incident on respective positions on the reflecting surface of the reflecting mirror. Since the reflecting surface is curved, respective group delay times corresponding to the wavelengths are provided according to the wavelengths at the time of reflection, whereby the chromatic dispersion of light is adjusted.